Message type: E = Error
Message class:  FICUSTOM - Customizable Messages for Funds Management 
Message number: 287
Message text: WBS element is already used in a different document
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The SAP error message FICUSTOM287 indicates that a Work Breakdown Structure (WBS) element is already being used in a different document. This typically occurs in the context of project management and financial transactions where WBS elements are utilized to track costs and revenues associated with specific projects.
Cause: WBS Element Already Assigned: The WBS element you are trying to use is already assigned to another document, such as a purchase order, sales order, or another project-related document. Document Type Restrictions: Certain document types may have restrictions on the reuse of WBS elements, leading to conflicts when trying to assign the same WBS element to multiple documents. Incorrect Document Flow: The document flow may not be correctly set up, causing the system to recognize the WBS element as already in use.
Solution: Check Document Assignment: Verify which document the WBS element is currently assigned to. You can do this by using transaction codes like CJ20N (Project Builder)
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